A typical automated data storage library comprises storage shelves for storing data storage cartridges, data storage drives for reading and/or writing with respect to the data storage cartridges, and one or more pickers for accessing the data storage cartridges with respect to the storage shelves and data storage drives. The picker is typically moved in a predetermined path along a set of tracks or at the end of a swing arm. If a swing arm, the library is in the form of a cylinder and the maximum size of the library is typically fixed, and additional libraries or pass-through ports must be added if additional capacity is required. If a set of tracks are employed to guide the picker, the picker typically comprises a carriage that rides on the tracks. Additional capacity may be added by extending the tracks, for example, by adding a frame having tracks and storage shelves.
The carriage typically trails a cable which is coupled at the trailing end to the library, over which power and communications are provided to the picker. Thus, when the library is extended, in addition to extending the tracks, the trailing cable is replaced with a longer cable, to allow the picker carriage to go the additional distance along the tracks, incurring additional cost and waste. Further, the path of the tracks and the carriage must be straight or nearly so, so that the trailing cable will stay in the path. Still further, it is difficult to have multiple paths, to insure that the trailing cable will not cross a track. These limitations result in the requirement that an expandable library is a long rectangle.
Other methods than a trailing cable have been suggested. One example comprises U.S. Pat. No. 6,089,512, which proposes an inductive power transmitter and a parallel data communication antenna for a track guided transport system. In one embodiment, the power and data transmission are the same system. The system is designed for movement of assembly parts for an automotive plant or of pallets for high shelf storage facilities, both of which are fixed in size. The inductive power transmitter is a continuous, seamless, linear “primary circuit”.
Such a system is not easily adaptable to an automated data storage library that may be expanded, since the power transmitter would have to be redesigned and rebuilt to accommodate the additional size of the library, for example, due to the different attenuation characteristics of the different length. Additionally, the continuous, seamless “primary circuit” would prevent the possibility of multiple paths.